Deltas
erosion
sand dunes
(not sure about this one) key currents
Answer:
Scientists often use models of Earth to study the movement of earth and it's moon. They figure out what the distance is from the moon to the point between earth and moon where the gravitational pulls of earth and moon are equal.
Answer: B. Fox nests
Explanation:
Foxes dig out dens to provide a safe underground space that is mostly used for raising fox cubs, also called kits. In urban areas, the dens - known as earths - are commonly located under sheds, but they can also be among tree roots, in bushes or on railway embankments.
Answer:
An experiment that directly test the hypothesis.
Explanation:
Although there is quite a bit missing from Mary's scientific investigation, the thing that sticks out the most is the fact that Mary is missing an experiment. Mary's hypothesis states that people would fall asleep faster if their room color were to be painted blue. To prove that her hypothesis is true, Mary would need to conduct an experiment to see whether or not she was correct.